Circular  No.  108. 

I  nited  States  Departme 


BUREAU  OF   ENTO 
L.  O.   HOWARD.   Entomologist  and 


HOI  SI.    FLEAS. 

Bj    l.    O.   How  \w>. 

.Iuil£rin£r  from  the  specimens  of  1 1  * • : » —  sent  to  t ho  Bureau  of  Ento- 
mology of  recent  years  with  complaints  of  houses  being  infested  by 
them,  the  human  flea  {Pview  irritant  L.)  is  not  the  species  most  likely 


Fio.  1. — Cat  and  dog  Sea  (Ctenocephahu  canto)  :  >/.  Egg;  '».  tarn  In  cocoon;  '.  pupa:  J, 
adult  ;   i',  mouth  par-  from  tide  ;  /.  ■/.  labium   tram   below       '■ 

Ifnch  enlarged  .  more  enlarged.     (Author's  Illustration,  redrawn.) 

to  occur  in  great  numbers  in  dwelling  houses  in  1 1  * i  —  eountry,  but 
rather  the  common,  cosmopolitan  flea  of  the  d<  g  and  cal     I 
cephahu    cants   Curtis).*     This    holds   especially    for    the    eastern 


n  In  the  earlier  publications  of  thN  office,  Bulletin   i  and  circular  18,  tins 
species  has  been  referred  to  under  the  name  P  Oerv. 

88200    l 


United  States.  Pulex  irritam  is  sometimes  found  in  houses  in 
California,  and  is  the  prevailing  household  flea  of  Europe.  A  house 
may  become  infested  with  the  eat  and  dog  flea  even  though  no 
domestic  animals  be  kept,  for  a  visitor  at  a  house  where  such  pets 
are  maintained  may  be  the  means  of  carrying  home  with  him  one  or 
two  female  fleas  which  will  stock  his  own  premises.  Of  course,  where 
a  pet  dog  or  cat  is  kept,  the  source  of  the  infestation  is  manifest. 

The  worst  case-  of  infestation  reported  to  this  Bureau  have  usually 
been  those  in  which  houses  had  been  temporarily  unoccupied  during 
the  summer.  Such  houses  during  a  rainy  summer  become  more  or 
less  dam]),  and  as  a  rule  the  customary  sweeping  of  the  floor-  i-  inter- 
rupted, thus  furnishing  the  very  conditions  under  which,  as  we  shall 
see.  fleas  most  readily  propagate. 

The  eggs  (fig.  1,  a)  of  Ctenocephalus  canis  are  deposited  among  the 
hairs  of  cats  and  dogs,  but  as  they  are  not  attached  to  the  hairs, 
numbers  drop  off  whenever  the  infested  animal  moves  or  lie-  down. 
From  these  eggs  hatch  the  larvae  (fig.  2.  a),  which  are  -lender. 
minute,  white,  wormlike  creature-.  They  are  very  active,  crawl  rapidly, 
penetrate  into  the  cracks  of  the  floor,  and  live  there  until  full  grown, 
feeding  upon  such  organic  matter  as  may  have  collected  in  the 
cracks.  They  develop  rapidly,  and  in  midsummer  in  Washington 
reach  full  growth  in  a  short  time.  On  reaching  full  growth  the 
larva  spins  a  delicate,  white,  silken  cocoon  (fig.  1.  7j).  and  transform- 
to  pupa  (fig.  1,  c).  the  adults  (fig.  1.  d)  issuing  a  few  days  later. 
A  whole  generation  may  develop  in  the  course  of  a  fortnight  in  warm, 
damp  weather,  but  a  great  excess  of  moisture  results  in  the  destruc- 
tion of  the  larva>.  With  this  rapid  development  under  the  most 
favorable  conditions,  a  housekeeper,  shutting  up  her  house  in  June, 
for  example,  with  a  colony  of  fleas  too  small  to  be  noticed  inside  the 
house,  should  not  be  surprised  to  find  the  establishment  overrun  with 
fleas  when  she  opens  it  again  in  September  or  October. 

KEMEDIK-. 

If  you  do  not  desire  to  be  troubled  by  fleas,  do  not  keep  cats  or  dogs. 
If  you  must  keep  a  pet  dog  or  cat.  provide  a  rug  for  the  animal  to 
sleep  on,  and  give  this  rug  a  frequent  shaking  and  brushing,  after- 
wards sweeping  up  and  burning  the  dust  thus  removed.  As  all  the 
flea  eggs  on  an  infested  animal  will  not.  however,  drop  off  in  this  way. 
and  as  those  which  remain  on  it  will  probably  develop  successfully, 
it  will  be  found  wise  to  occasionally  rub  into  the  hair  of  the  dog  or 
cat  a  quantity  of  pyrethrum  powder.  If  thoroughly  applied,  this 
powder  will  cause  the  fleas  to  fall  off  in  a  half  stupefied  condition, 
when  they,  too,  may  be  swept  up  and  burned. 

The  larva?  of  the  dog  and  cat  flea  will  not  develop  successfully  in 
situations  where  they  are  likely  to  be  disturbed.  The  use  of  carpets 
[Cir.  iosj 


3 


:t 1 1 1 1  -daw  mattings,  in  the  writer's  opinion,  favors  their  development, 
since  the  young  larvae  can  penetrate  the  interstices  of  either  botI  of 
floor  covering  and  find  an  abiding  place  in  some  crack  where  they  are 
not  likely  to  be  disturbed.  It  is  comparatively  easj  t"  destroy  the 
insect  in  its  earlj  stages  (when  it  is  noticed),  but  the  adult  fleas  are 
so  active  and  so  hardy  that  they  successfully  resist  any  but  1 1 » « -  most 
strenuous  measures.  Even  the  persistent  use  of  California  buhacb 
ami  oilier  |>\  Tethrum  powders  was  ineffectual  in  one  case  ><(  extreme 
infestation,  a-  was  also,  and  more  remarkably,  a  free  sprinkling  of 
floor  mattings  with  benzine.  In  tin-  instance  it  was  finally  necessan 
to  take  up  the  floor-coverings  and  wash  the  floors  down  with  hoi 
psuds  i:i  order  to  secure  relief  from  the  ilea  plague.  In  another 
case,  however,  a  single  liberal  application  of  buhach  was  perfectlj 
successful,  while  in  a  third  a  single  thorough  application  of  benzine 
completely  rid  an  infested  house  id'  Ilea-. 

In  had  cases  almost  nothing  will  avail  without  the  greatest  care  in 
keeping  the  floor  and  other  coverings,  a-  well  a-  crevices,  etc..  free 
from  dust  and  dirt.  The  old  remedy  often  mentioned  of  putting  a 
piece  of  raw    meat    upon  a  -heel   id'  Micky   il\    paper,  in  the  hope  that 

the  fleas  will  jump  for  the  meat  and  lie  caught  by  the  il\  paper,  has 
been  thoroughly  tried  by  the  writer  without  success.    Where  their  arc 

comparatively  few  Ilea-  in  a  house  or  in  a  given  room,  the  following 
somewhat  laborious  plan  will  result  in  eradication.  Place  a  white 
cloth,  like  a  pillowcase,  in  the  middle  of  the  Moor.  The  fleas,  attracted 
by  the  white  color,  will  jump  on  the  cloth.  Then,  with  a  basin  of 
water,  kneel  down  and  with  the  wetted  forefinger  pick  up  the  flea- 
one  after  another  and  put  them  in  the  water.  The  writer  ha-  known 
several  houses  in  Washington  to  he  rid  of  rather  sparse  populations 
of  Ilea-  in  this  manner. 

Mi.  E.  M.  Ehrhorn,  of  San  Francisco,  gives  the  following  remedy, 
which  he  -tate-  he  has  tested  and  which  hi-  mother  used  with  effect 
in  South  America.  Fill  a  glass  three  fourth-  with  water,  on  top 
of  which  pour  about  an  inch  of  olive  oil.  then  place  a  night  float  (a 
little  wick  inserted  in  a  cardboard  disk  or  in  a  cork  disk)  in  the 
center  of  the  oil.  Place  the  tumbler  in  the  center  of  a  SOUp  plate 
filled  with  strong  soapsuds.  The  wick  should  he  lighted  at  night  on 
retiring,  or  may  he  used  in  any  dark  room.  A-  the  soup-plate-soap- 
-  trap  i<  placed  on  the  floor  of  the  room  it  doe-  not  interfere  with 
the  sleeper,  and  the  flea-  which  arc  on  the  floor  arc  attracted  to  the 

light.  For  outbuildings,  such  a-  ham-,  etc,  a  large  milk  pan  may 
he  used,  and  instead  of  using  olive  oil  anil  a  glass,  a  stable  lantern 
may  he  placed  in  the  center  id'  the  pan,  while  instead  of  soapsuds  a 
-cum  of  kerosene  may  he  put  on  the  water  in  the  milk  pan. 

[Clr 


UNIVERSITY  OF   FLORIDA 


3  1262  09216  5280 

To  sum  up:  Every  house  where  a  pet  dog  or  cat  is  kept  may  be- 
come seriously  infested  with  fleas  if  the  proper  conditions  of  moisture 
and  freedom  from  disturbance  exist.  Infestation,  however,  is  not 
likely  to  occur  if  the  (bare)  doors  can  be  frequently  and  thoroughly 
swept.    When  an  outbreak  of  fleas  comes,  however,  the  easiest  remedy 

to  apply  is  a  free  sprin- 
kling of  pyrethruni  pow- 
der in  the  infested  rooms. 
This  failing,  benzine  may 
be  tried,  a  thorough  spray- 
ing of  carpets  and  floors 
being  undertaken,  with 
the  exercise  of  due  pre- 
caution in  seeing  that  no 
lights  or  fires  are  in  the 
house  at  the  time  of  the 
application,  or  for  some 
hours  afterwards.  Final- 
ly, if  the  plague  is  not 
thus  abated,  all  floor  cov- 
erings must  be  removed 
and  the  floors  washed  with  hot  soapsuds.  This  is  a  useful  precaution 
in  any  house  which  it  is  proposed  to  close  for  the  summer,  since  even 
a  thorough  sweeping  may  leave  behind  some  few  flea  eggs  from  which 
an  all-pervading  swarm  may  develop  before  the  house  is  reopened. 

Approved : 

James  WlLSON, 

Secretary  of  Agriculture. 

Washington.  D.  C,  December  29,  1908. 

[Cir.  1081 

O 


Fig.  2. — Cat  and  dog  flea  {Ctenoeephalus  canis)  :  «. 
Larva  ;  h,  head  of  same ;  c,  anal  end  of  same.  a. 
Much  enlarged;  h,  c,  more  enlarged.  (Authors 
illustration,  redrawn.) 


